A cone-beam computed tomography evaluation of missed canals in endodontically treated teeth in Central India...

Missed root canals are a common cause of endodontic failure and are often related to complex root canal anatomy that cannot be adequately visualized using conventional radiography. Cone-beam computed tomography (CBCT) allows three-dimensional assessment and improves the detection of untreated canals.

The aim of this study was to determine the prevalence of missed canals in endodontically treated mandibular first molars in a Central Indian population and to evaluate their association with extra roots.

This retrospective cross-sectional study evaluated 400 CBCT scans of endodontically treated mandibular first molars obtained from government and private imaging centers in Central India. Canals appearing unfilled from the cementoenamel junction to the apex were recorded as missed canals. The presence of extra roots was also assessed. Data were analyzed using the Chi-square and Fisher's exact tests, with statistical significance set at P < 0.05.

Missed canals were detected in 88 teeth, representing a prevalence of 22.0%. Extra roots were identified in 15 (3.75%) teeth, of which 11 (73.3%) exhibited missed canals. Teeth with extra roots showed a significantly higher prevalence of missed canals compared to those without extra roots (73.3% vs. 20.0%; χ² = 20.92, P < 0.001), with an 11-fold increased odds (odds ratio = 11.0). No significant association was observed between gender and missed canals (P = 1.00).

CBCT revealed a high prevalence of missed canals in mandibular first molars, with extra roots significantly increasing the risk. These findings emphasize the clinical value of CBCT in detecting anatomical complexities and preventing endodontic treatment failure.